Hi all, I recently had a cel on only stayed on for about 15 mins . Then went off. I read it a few days later(after it went off) and it said ego not switching to lean bank 1 . Is this an O2 sensor? I will add I've had a hesitiation /stumble sometimes stall after truck sits 8-10hrs after initial drive . (When leaving work) it doesn't do it as much anymore but sometimes still does. It's been ongoing for about a year. I've replaced within the last yr. TPS,air filter,p/s pump(not related to this issue),belt tensioner, belt,cleaned the IAC numerous times, oil and filter, fuel filter, plug wires . If anyone has any ideas please let me know. Thanks.

 

Check fuel psi.

The 4.9 needs 50 psi to run well. If it's 45 or below, it'll cause that code.

 

Okay . What causes low fuel pressure? I ran sea foam since after adding the new filter. Maybe the filter is getting plugged up again?

 

Hi again. So do I need to change my o 2 sensor? Sorry for the inexperience . Not a mechanic by any means... Thanks...

 

...did you ever check your fuel pressure?